Cancer is a term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several types of cancer, including without limitation, carcinoma which is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.
The human carcinoembryonic Ag (CEA)3 protein family encompasses several proteins with different biochemical features. These proteins are encoded by 29 genes tandemly arranged on chromosome 19q13.2. CEA family genes have been classified into two major subfamilies, the CEA cell adhesion molecule (CEACAM) and the pregnancy-specific glycoprotein subgroups. The CEACAM proteins, which are part of the larger Ig superfamily, include CEACAM1, −3, −4, −5, −6, and −8. They share a common basic structure of sequentially ordered different Ig-like domain(s) and are able to interact with each other. For example, it has been reported that various CEACAM proteins, such as CEACAM1 or CEACAM5, exhibit both homophilic and heterophilic interactions.
CEACAM1 (CD66a), a transmembrane protein and member of the carcinoembryonic Ags family (belongs to IgSF), contains two ITIM sequences located within its cytosolic tail. CEACAM1 interacts with other known CD66 proteins (both homophilic and heterophilic interactions), including CD66a, CD66c, and CD66e proteins. It is expressed on a wide spectrum of cells, ranging from epithelial to hemopoietic origin. Among CD66 proteins tested, only the CD66a protein is expressed on the surface of activated CD16-negative NK cells.
Point-of-care testing refers to a medical test which is carried out at sites other than a central laboratory, and comprises testing at or near the site of patient care. The value added by Point-of-Care Diagnostics is significant, and includes for example: improved patient outcomes attributable to immediate on-site actionable healthcare resulting from immediate test results (i.e.—reduced time for start of treatment); access to areas lacking clinical laboratory infrastructures (i.e.—rural areas, disaster areas, and developing countries); and avoidance of sample identification and sample transport problems.